<?php

/*
 * This file is part of SwiftMailer.
 * (c) 2004-2009 Chris Corbyn
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

/**
 * A MIME part, in a multipart message.
 *
 * @package    Swift
 * @subpackage Mime
 * @author     Chris Corbyn
 */
class Swift_Mime_MimePart extends Swift_Mime_SimpleMimeEntity
{
	/** The format parameter last specified by the user */
	protected $_userFormat;

	/** The charset last specified by the user */
	protected $_userCharset;

	/** The delsp parameter last specified by the user */
	protected $_userDelSp;

	/** The nesting level of this MimePart */
	private $_nestingLevel = self::LEVEL_ALTERNATIVE;

	/**
	 * Create a new MimePart with $headers, $encoder and $cache.
	 *
	 * @param Swift_Mime_HeaderSet $headers
	 * @param Swift_Mime_ContentEncoder $encoder
	 * @param Swift_KeyCache $cache
	 * @param Swift_Mime_Grammar $grammar
	 * @param string $charset
	 */
	public function __construct(Swift_Mime_HeaderSet $headers, Swift_Mime_ContentEncoder $encoder, Swift_KeyCache $cache, Swift_Mime_Grammar $grammar, $charset = null)
	{
		parent::__construct($headers, $encoder, $cache, $grammar);
		$this->setContentType('text/plain');
		if (!is_null($charset)) {
			$this->setCharset($charset);
		}
	}

	/**
	 * Set the body of this entity, either as a string, or as an instance of
	 * {@link Swift_OutputByteStream}.
	 *
	 * @param mixed $body
	 * @param string $contentType optional
	 * @param string $charset optional
	 *
	 * @return Swift_Mime_MimePart
	 */
	public function setBody($body, $contentType = null, $charset = null)
	{
		if (isset($charset)) {
			$this->setCharset($charset);
		}
		$body = $this->_convertString($body);

		parent::setBody($body, $contentType);

		return $this;
	}

	/**
	 * Get the character set of this entity.
	 *
	 * @return string
	 */
	public function getCharset()
	{
		return $this->_getHeaderParameter('Content-Type', 'charset');
	}

	/**
	 * Set the character set of this entity.
	 *
	 * @param string $charset
	 *
	 * @return Swift_Mime_MimePart
	 */
	public function setCharset($charset)
	{
		$this->_setHeaderParameter('Content-Type', 'charset', $charset);
		if ($charset !== $this->_userCharset) {
			$this->_clearCache();
		}
		$this->_userCharset = $charset;
		parent::charsetChanged($charset);

		return $this;
	}

	/**
	 * Get the format of this entity (i.e. flowed or fixed).
	 *
	 * @return string
	 */
	public function getFormat()
	{
		return $this->_getHeaderParameter('Content-Type', 'format');
	}

	/**
	 * Set the format of this entity (flowed or fixed).
	 *
	 * @param string $format
	 *
	 * @return Swift_Mime_MimePart
	 */
	public function setFormat($format)
	{
		$this->_setHeaderParameter('Content-Type', 'format', $format);
		$this->_userFormat = $format;

		return $this;
	}

	/**
	 * Test if delsp is being used for this entity.
	 *
	 * @return boolean
	 */
	public function getDelSp()
	{
		return ($this->_getHeaderParameter('Content-Type', 'delsp') == 'yes')
			? true
			: false;
	}

	/**
	 * Turn delsp on or off for this entity.
	 *
	 * @param boolean $delsp
	 *
	 * @return Swift_Mime_MimePart
	 */
	public function setDelSp($delsp = true)
	{
		$this->_setHeaderParameter('Content-Type', 'delsp', $delsp ? 'yes' : null);
		$this->_userDelSp = $delsp;

		return $this;
	}

	/**
	 * Get the nesting level of this entity.
	 *
	 * @see LEVEL_TOP, LEVEL_ALTERNATIVE, LEVEL_MIXED, LEVEL_RELATED
	 *
	 * @return int
	 */
	public function getNestingLevel()
	{
		return $this->_nestingLevel;
	}

	/**
	 * Receive notification that the charset has changed on this document, or a
	 * parent document.
	 *
	 * @param string $charset
	 */
	public function charsetChanged($charset)
	{
		$this->setCharset($charset);
	}

	// -- Protected methods

	/** Fix the content-type and encoding of this entity */
	protected function _fixHeaders()
	{
		parent::_fixHeaders();
		if (count($this->getChildren())) {
			$this->_setHeaderParameter('Content-Type', 'charset', null);
			$this->_setHeaderParameter('Content-Type', 'format', null);
			$this->_setHeaderParameter('Content-Type', 'delsp', null);
		} else {
			$this->setCharset($this->_userCharset);
			$this->setFormat($this->_userFormat);
			$this->setDelSp($this->_userDelSp);
		}
	}

	/** Set the nesting level of this entity */
	protected function _setNestingLevel($level)
	{
		$this->_nestingLevel = $level;
	}

	/** Encode charset when charset is not utf-8 */
	protected function _convertString($string)
	{
		$charset = strtolower($this->getCharset());
		if (!in_array($charset, array('utf-8', 'iso-8859-1', ''))) {
			// mb_convert_encoding must be the first one to check, since iconv cannot convert some words.
			if (function_exists('mb_convert_encoding')) {
				$string = mb_convert_encoding($string, $charset, 'utf-8');
			} elseif (function_exists('iconv')) {
				$string = iconv($charset, 'utf-8//TRANSLIT//IGNORE', $string);
			} else {
				throw new Swift_SwiftException('No suitable convert encoding function (use UTF-8 as your charset or install the mbstring or iconv extension).');
			}

			return $string;
		}

		return $string;
	}
}
